如何合并两个Django QuerySets并进行SELECT DISTINCT

Question

models.py

class SinglePoint(models.Model):
    attributes = models.TextField(blank=True)
    name = models.CharField(max_length=100)
    geom = models.PointField() #Kartenposition
    objects = models.GeoManager()

class Connection(models.Model):
    name = models.CharField(max_length=100)
    #points = models.ManyToManyField(SinglePoint) #OLD
    p1 = models.ForeignKey(SinglePoint, related_name='p1_set') #NEW
    p2 = models.ForeignKey(SinglePoint, related_name='p2_set') #NEW
    obs = models.ManyToManyField(Observation, blank=True)
    conds = models.ManyToManyField(Condition, blank=True)
    objects = models.GeoManager()
  
class Meta:
    order_with_respect_to = 'p1'

在我的 view.py 文件中：

...
p1_points = SinglePoint.objects.filter(name=name)
p2_points = SinglePoint.objects.filter(name=name)
...

在我改用 ForeignKey 之前，它是这样工作的：

points = SinglePoint.objects.filter(name=name)

怎么把这两个查询结果合并成一个，并且去重呢？

谢谢！

Answer 1

我觉得Q 查询可以像这样满足你的需求：

points = SinglePoint.objects.filter(
    Q(name=name) |
    Q(name=name)
).distinct()

Answer 2

我对geodjango不太熟悉，不过可以通过Q对象和布尔运算符把多个查询集合并成一个查询集。你可以查看这个链接了解更多信息：http://docs.djangoproject.com/en/dev/topics/db/queries/#complex-lookups-with-q-objects

举个例子：

Q(p1_points) | Q(p2_points)

我无法进一步帮助你，因为我不太确定你想要实现什么。

Answer 3

我花了一些时间才找到这个

all_points = p1_points | p2_points